ipv6 nd learning prefix strict enable

Function

The ipv6 nd learning prefix strict enable command enables the strict prefix learning function for dynamic neighbor entries.

The undo ipv6 nd learning prefix strict enable command restores the default configuration.

By default, an interface is not enabled with the strict prefix learning function for dynamic neighbor entries. The interface behavior is consistent with the configuration in the system view.

Format

ipv6 nd learning prefix strict enable

undo ipv6 nd learning prefix strict enable

Parameters

None

Views

100ge sub-interface view, 100GE interface view, 10GE sub-interface view, 10GE interface view, 200GE sub-interface view, 25GE sub-interface view, 25GE interface view, 400GE sub-interface view, 400GE interface view, 40GE sub-interface view, 40GE interface view, 50GE sub-interface view, 50GE interface view, Eth-Trunk sub-interface view, Eth-Trunk interface view, FlexE interface view, GE optical interface view, GE sub-interface view, GE interface view, GE electrical interface view, Global VE sub-interface view, VE sub-interface view, Management interface view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
nd	write

Usage Guidelines

Usage Scenario

When a device receives a valid NS message on an interface, the device checks whether IPv6 addresses with the same network prefix exist on the interface. If so, the device replies with an NA message and generates dynamic neighbor entries. If not, the device performs the following operations:

If the strict prefix learning function for dynamic neighbor entries is enabled on the interface, the device simply discards the NS message and does not generate dynamic neighbor entries.
If the strict prefix learning function for dynamic neighbor entries is disabled on the interface, the device replies with an NA message and generates dynamic neighbor entries.

Prerequisites

The IPv6 function has been enabled using the ipv6 enable command.

Precautions

After the strict prefix learning function is enabled for dynamic neighbor entries, the device does not delete the learned dynamic neighbor entries corresponding to different address prefixes. Instead, the device waits for the entries to automatically age out.
The configuration of the strict prefix learning function for dynamic neighbor entries in the interface view has a higher priority than that in the system view.

Example

# Enable the strict prefix learning function for dynamic neighbor entries on GE0/1/1.

<HUAWEI> system-view
[~HUAWEI] interface GigabitEthernet 0/1/1
[~HUAWEI-GigabitEthernet0/1/1] ipv6 enable
[*HUAWEI-GigabitEthernet0/1/1] ipv6 nd learning prefix strict enable